Had service engine soon light read. What does the troubleshooting mean?

Done at autozone. This is what it said.

My car: 1999 Mercury Sable GS

Troubleshooting P0113

OEM Brand: Ford

Definition:

Intake Air Temperature (IAT) sensor circuit high input.

Explanation- ECM has detected a high voltage condition on the IAT circuit.

Probable cause-
1.Open or short circuit condition.
2.Poor electrical connection.
3.Faulty IAT sensor.

What does all of this mean in layman's terms. Also how bad is it ? Thanks :)

there would not be a short circuit.....that would cause low voltage on thermistor signal wire.......you either have an open signal wire.....bad thermistor or an open ground.you could backprobe with t pins both wires at iat and check voltage on both wires.....if you have high voltage on both wires at connector you have an open ground.....you could check resistance of the iat and compare the resistance value with the ambient temperature with engine cold.send me an email and i can email that to you.if you dont have 5 volts on signal wire to thermistor then you have an open signal wire which is the gray wire.also check the connector that it is making good connection.the gray/red wire is sensor ground which feeds other sensors also.more than likely bad open thermistor.without testing you dont know.a scan tool is best way to test to see what pcm is seeing.